Derive pubsub example in docs is not working

[nazar-pc]

I've copy-pasted the example given (even though it is not complete) and got this compile-time error:

error[E0271]: type mismatch resolving `<jsonrpc_pubsub::IoDelegate<sub::RpcImpl, Arc<Session>> as IntoIterator>::Item == (std::string::String, RemoteProcedure<()>)`
  --> src/rpc.rs:95:8
   |
95 |     io.extend_with(sub::RpcImpl::default().to_delegate());
   |        ^^^^^^^^^^^ expected struct `Arc`, found `()`
   |
   = note: expected tuple `(std::string::String, RemoteProcedure<Arc<Session>>)`
              found tuple `(std::string::String, RemoteProcedure<()>)`

I'm using current git master because I don't want to mess with futures 0.1.

Any ideas what is wrong here? Also having a full example in there would help to make sure it doesn't regress.

UPD: Seems to be caused by IoHandler::new(); instead of PubSubHandler::new(MetaIoHandler::default()), but now a new error:

error[E0277]: the trait bound `Session: Default` is not satisfied
  --> src/rpc.rs:82:37
   |
82 |     let server = ServerBuilder::new(io)
   |                                     ^^ the trait `Default` is not implemented for `Session`
   | 
  ::: /home/nazar-pc/.cargo/git/checkouts/jsonrpc-22a65938f7d26b63/92e3c14/ws/src/server_builder.rs:37:12
   |
37 |         T: Into<core::MetaIoHandler<M, S>>,
   |            ------------------------------- required by this bound in `ServerBuilder::<M, S>::new`
   |
   = note: required because of the requirements on the impl of `Default` for `Arc<Session>`

UPD 2: pubsub/examples/pubsub.rs is also broken, starting with context.sender.clone() that needs to be context.sender() to there is no such thing as an acquire/release load for obvious reasons; did it ever work at all?

[tomusdrw]

@nazar-pc Could you clarify which example do you mean?

1. The first error indeed like using IoHandler in pub-sub examples (Metadata defaults to ())
2. To overcome the second error you need to use ServerBuilder::with_meta_extractor.

The reason for this is that pubsub requires the Session object to be created by the transport layer (so that we can push updates to the client) - there is no Default there.

[nazar-pc]

I'm talking about Pub/Sub Example here: https://docs.rs/jsonrpc-derive/15.0.0/jsonrpc_derive/

[tomusdrw]

Closed by #588